Enrique put a large emphasis on the role played by the crowd at the Camp Nou will play: Getty

You could say that Luis Enrique was being fanciful, even delusional, except we’ve already seen something even more incredible before.

Just as on the eve of his team’s 6-1 comeback against Paris Saint-Germain, the Barcelona manager was talking with an impressively assured matter-of-factness about how another “miracle” could rather logically take place ahead of his side’s Champions League quarter-final second leg against Juventus.

The scenario he put forward for how the game could pan out, as the Spanish champions seek to overturn a 3-0 deficit, was once again entirely plausible.

“The tie can turn around,” Luis Enrique said. “If we score the first in the first minute, the second is scored by the stadium, and the third falls by itself.”

Then it’s up for grabs, as easy as that.

It won’t be that easy, of course, but the Barca manager did touch on something that was perfectly illustrated by the PSG game, and is just as important as his side’s greater application from the energising knowledge they have done something like this before: the effect of “momentum” in such games, and how its psychological state is influenced by any goals.

If Barca score one early goal, after all, the match is suddenly not about an epic and barely comprehensible comeback. It becomes much more distilled, much more intense. It instead becomes about Juventus holding their nerve in a cauldron that only gets hotter with every home attack.

That was a challenge PSG spectacularly failed.

The other side of that beyond Barca first having to breach that brilliant defence, however, is that Juventus are not PSG. They are much stronger, both in terms of how cohesive they are as a team collective and in mentality.

If Barca do get that early goal, it is impossible to imagine a defence featuring Giorgio Chiellini and Leo Bonucci pathetically panicking in the way the French champions did. They just have that sturdiness and reliability PSG never did, as perfectly evidenced by Bonucci’s challenge on Luis Suarez in the first leg, or the manner that Chiellini so defiantly punched the air after another crucial block.

And yet, the oddity of that match was that Barca were far from at their best but still created the better chances and could actually have turned around the 3-0 deficit on the night. They had enough high-quality chances. Suarez on his own could have made this a much nervier second leg for Juve, given that he could so easily have made it 3-2.

If Barca can improve on that even a little, it can genuinely go a long way, and make this a long night for Juve.

View photos

Messi was far from perfect in the first leg (Getty)

Then there was the ominous form of Leo Messi. He didn’t score in Turin, and was far from perfect, but some of his more productive moves - like that pass for Andres Iniesta - suggested a player in the determined mindset to make up for recent drop; to rectify a few wrongs.

It also remains one of the fundamental truths in European football, since he remains one of its finest individual forces: if Messi is properly on it, then all bets are off. Almost anything is possible. He is the sort of player that can make a resounding win over a rival suddenly seem so routine, albeit through the Argentine doing the extraordinary for everyone else. Everyone from Real Madrid to Bayern Munich can testify to that.

The problem for Messi and the rest of the Barca attack is that, even if they are on it, the wonder will be whether the same can be said of their defence. Juve and especially Paulo Dybala found it so easy to get at. The Catalans just seem highly unlikely to keep a clean sheet, as Luis Enrique effectively admitted.

“Our objective is to score five goals in case they score as well.”

At the very least, Sergio Busquets is back, and that does completely change how commanding Barca are behind the midfield. The hope for them is that their attack can be on such focused form that they pin Juve back so they can barely get near Andre ter Stegen’s goal because, even allowing for momentum and psychological swings in such matches, properly hammering a side like Juve by more than four goals is very different to even just getting the three against them to go level.

This is going to require a different level, probably even to what happened against PSG.

As incredible as brilliant as that comeback was, it was still something of a freak occasion, amplified by how fragile the French were.

Barca have to be even better than that night, to pull off a comeback that isn’t fundamentally as big, but still looks so much more difficult. That's the stark reality, but may need almost-deluded belief to pull off.